Truffles don’t particularly taste like much, but their smell is euphoric. It’s their relative rarity combined with this blissful aroma that makes those little fungal nubs one of the most expensive delicacies in the world, often selling for hundreds of dollars per pound.
Now, Italian scientists have begun to crack the mystery of that unique truffle scent. As BBC Earth reports, they found that black truffles produce a natural chemical similar to the tetrahydrocannabinol, the psychoactive compound found in majijuana. Described by BBC Earth as a “bliss molecule,” anandamide, the black truffle equivalent, causes the brain to release mood-enhancing chemicals. This effect isn’t just confined to humans, either. According to the researchers, various mammals are likely susceptible to this chemical trick, too. This probably explains why truffle-sniffing dogs and hogs seem to fall under a frenzied spell when they begin to home in on one of those delectable subterranean treasures, BBC Earth reports.
So why do the truffles make anandamide? The truffles, the researchers found, do not have the requisite receptors that anandamide binds to, meaning the fungus itself has no use for the chemical. Given that, the researchers think that black truffles likely evolved this chemical profile precisely to encourage animals to devour them, BBC Earth writes. As the anandamide-intoxicated animal eats the truffle, the fungus’ tiny spores are probably spread over a wider area than they would be if they just sat in the earth on their own.
Determining whether white, burgundy, and Bianchetto truffles also evolved the same propagation-friendly chemical profile will require further tests.